a perpetual motion machine that will work.... A magazine held a competition, inviting its readers to submit new scientific theories on ANY subject. Below is the winner: Subject: Perpetual Motion When a cat is dropped, it always lands on its feet, and when toast is dropped, it always lands buttered side down. Therefore, if a slice of toast is strapped to a cat's back, buttered side up, and the animal is then dropped, the two opposing forces will cause it to hover, spinning inches above the ground. If enough toast-laden felines were used, they could form the basis of a high-speed monorail system. ......... and then this mail got this reply from one of the readers I've been thinking about this cat/toast business for a while. In the buttered toast case, it's the butter that causes it to land buttered side down - it doesn't have to be toast, the theory works equally well with Jacob's crackers. So to save money you just miss out the toast - and butter the cats. Also, should there be an imbalance between the effects of cat and butter, there are other substances that have a stronger affinity for carpet. Probability of carpet impact is determined by the following simple formula: p = s * t(t)/t(c) where p is the probability of carpet impact s is the "stain" value of the toast-covering substance - an indicator of the effectiveness of the toast topping in permanently staining the carpet. Chicken Tikka Masala, for example, has a very high s value, while the s value of water is zero. t(c) and t(t) indicate the tone of the carpet and topping - the value of p being strongly related to the relationship between the colour of the carpet and topping, as even chicken tikka masala won't cause a permanent and obvious stain if the carpet is the same colour. So it is obvious that the probability of carpet impact is maximised if you use chicken tikka masala and a white carpet - in fact this combination gives a p value of one, which is the same as the probability of a cat landing on its feet. Therefore a cat with chicken tikka masala on its back will be certain to hover in mid air, while there could be problems with buttered toast as the toast may fall off the cat, causing a terrible monorail crash resulting in nauseating images of members of the royal family visiting accident victims in hospital, and politicians saying it wouldn't have happened if their party was in power as there would have been more investment in cat-toast glue research. Therefore it is in the interests, not only of public safety but also public sanity, if the buttered-toast-on-cats idea is scrapped, to be replaced by a monorail powered by cats smeared with chicken tikka masala floating above a rail made from white shag pile carpet.